The present invention relates to a clamping chuck, such as is customarily connected with a rotary-driven spindle of a machine tool, and to a clamping chuck with receives a collet chuck. The collet chuck in turn holds a tool, for example a drill.
The known clamping chucks display certain asymmetries in their structure regarding the axis of rotation, in particular in that mostly a so-called "eccentric" is provided which engages a groove of the collet chuck for loosening the collet chuck, so that with the help of the eccentric the collet chuck cannot be loosened from its clamping with the clamping chuck. It is not possible to loosen the collet chuck without such an eccentric or corresponding pressure means gripping behind the collet chuck at a place along its circumference.
Such asymmetric components of a clamping chuck have the serious disadvantage that they cause an imbalance. This imbalance leads to vibrations at certain rpm. This results in a poor surface and impairs the service life of the tool. Furthermore, with the known systems the collet chuck is torsionally stressed, because on the one hand it is already clamped in a conical receptacle and, on the other hand, the adjusting nut places a torque on the collet chuck because of friction during clamping. Further concentricity errors are prevented by means of this.